"```html

<script src=\"script.js\"></script>

body {
    font-family: Arial, sans-serif;
    background-color: #f0f0f0;
    margin: 0;
    padding: 0;
}

.container {
    width: 80%;
    max-width: 400px;
    margin: 50px auto;
    padding: 20px;
    background-color: #fff;
    border-radius: 5px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

h1 {
    text-align: center;
}

form {
    display: flex;
    flex-direction: column;
}

label {
    margin-bottom: 5px;
}

input {
    padding: 8px;
    margin-bottom: 10px;
}

button {
    padding: 8px;
    background-color: #007bff;
    color: #fff;
    border: none;
    border-radius: 5px;
    cursor: pointer;
}

button:hover {
    background-color: #0056b3;
}

const form = document.getElementById('loginForm');

form.addEventListener('submit', function(event) {
    event.preventDefault();
    
    const username = document.getElementById('username').value;
    const password = document.getElementById('password').value;
    
    if(username === 'admin' && password === 'password') {
        alert('Login successful!');
    } else {
        alert('Invalid username or password. Please try again.');
    }
});
```"